System for a linear drive

ABSTRACT

A system, whereby drive units on a movable part, e.g., a turntable or linear drive, are powered in a contactless manner via, in each instance, an inductive coupling to one or more primary conductors.

FIELD OF THE INVENTION

The present invention relates to a system.

BACKGROUND INFORMATION

In industrial systems, it is conventional that drive units can bepowered from a network. For this purpose, drive units are mostlyconnected via expensive plug-and-socket connectors. In addition, thesystem or machine has a T-piece for each drive unit as an energy branch.These T-pieces are difficult to install and expensive, in particularwhen they must be usable and provide a high degree of protection in wetareas or even aseptic areas.

SUMMARY

Example embodiments of the present invention may provide simpler andmore cost-effective wiring in drive units and systems.

In the case of the system, features of example embodiments of thepresent invention include that it includes drive units, which arepowered on a movable part, e.g., a turntable or linear drive, in acontact-free manner, using, in each instance, an inductive coupling toone or more primary conductors. In this context, it may be provided thatthe wiring may be implemented simply and rapidly and, in addition, in awell-arranged manner. Moreover, the system may be used in wet areas andin aseptic areas, since the inductive coupling allows the housing to bemanufactured to be smooth. Furthermore, power is transmitted in anerosion-free manner.

It may also be provided that the power supply to the drive units isvoltageless, and that the carrying-over of voltage otherwise present insystems, as well as spark-suppression devices in disconnecting switches,may be eliminated. In addition, reactive-power compensation is madepossible, e.g., in the drive unit, and therefore the alternating currenthas smaller values, which is why smaller wire diameters may also beprovided in the case of primary conductors, and lower wiring costs aretherefore attainable. Disconnecting switches may be eliminated, sinceinterruption may be replaced by extraction of the primary conductor.

The part may be rotationally mounted or linearly movable. In thiscontext, it may be provided that the system may be manufactured as aturntable or a linear drive.

The primary conductor may power the drive units in series. This mayprovide that T-pieces are not necessary, and that highly cost-effectivewiring is implementable, e.g., without plug-and-socket connectors, etc.

Example embodiments may provide for the primary conductor to be suppliedwith energy in a contactless manner via stationary coil cores includingat least one coil winding, or to be supplied with energy via a loopwire. An aspect of the contactless transmission is that the movable partmay be used, in turn, in wet areas or aseptic areas, and that no erosionoccurs.

The primary conductor may be arranged as a closed loop. In this context,it may be provided that it is particularly cost-effective, and that nostarting pieces or end pieces are necessary.

At least one drive unit may include an electric motor and an electroniccircuit for powering the electric motor, the drive unit being able to bepowered inductively. In this context, it may be provided that the driveunit may be manufactured in a cost-effective manner to be impervious andto provide a high degree of protection, for the contactless powering ofthe drive unit may allow the housing to be manufactured simply andeasily, e.g., without uneven areas or plug-and-socket connectors, andtherefore may allow water to drain off and the settling of solids to beprevented. Therefore, it may be particularly usable in wet areas andaseptic areas. The time necessary for wiring may be reduced.

A primary conductor provided on the drive unit such that an inductivecoupling to a secondary winding contained by the drive unit isprovidable. In this context, it may be provided that a plug-and-socketconnector is not necessary, and that the wiring may therefore be carriedout in a simple and rapid manner. In addition, it is possible to reducecosts.

At least one primary conductor may be provided in a groove or a cableduct of the drive unit. In this context, it may be provided that thecable may be arranged very simply and rapidly, and that in addition,encapsulation with encapsulating material may be carried out.

At least one secondary winding may be wound around a U-shaped and/orE-shaped core. In this context, it may be provided that the design maybe selected as a function of the utilized method and desired efficiency.

The primary conductors may be at least partially encapsulated and/orprotected by a cover. This may provide that a particularly high degreeof protection is attainable.

The drive unit may be impervious, smooth on the outer surface, and/ormanufactured to have a high degree of protection. In this context; thedrive unit may be provided, e.g., for use in wet areas and/or asepticareas.

The drive unit may not include a plug-and-socket connector or otherelectrical connection terminals on its exterior. In this context, it maybe provided that the drive unit may be easily manufactured to beimpervious and to provide a high degree of protection.

LIST OF REFERENCE CHARACTERS

-   1 housing-   2 rotor shaft-   3 housing part-   4 primary conductor-   5 primary conductor-   6 indentation-   7 core having a U-shaped cross-section-   21 primary conductor-   22 primary conductor-   23 clip-   24 groove-   25 groove-   26 housing part-   27 core having a U-shaped cross-section-   28 second core having a U-shaped cross-section-   31 cover-   32 primary conductor-   33 primary conductor-   34 cable duct-   35 core having an E-shaped profile-   36 core having an E-shaped profile-   37 printed circuit board-   41 turntable-   42 turntable drive-   43 primary conductor-   44 drive unit-   45 stationary coil cores

Example embodiments of the present invention are explained in moredetail below with reference to the appended Figures.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1 a to 1 c illustrate a drive unit according to an exampleembodiment of the present invention.

FIGS. 2 a to 2 c illustrate a drive unit according to an exampleembodiment of the present invention.

FIGS. 3 a to 3 h illustrate a drive unit according to an exampleembodiment of the present invention.

FIG. 4 illustrates an example embodiment of the present invention.

FIGS. 5 a to 5 g illustrate an example embodiment of the presentinvention.

DETAILED DESCRIPTION

An isometric view, a sectional view, and a plan view of a drive unitaccording to an example embodiment of the present invention areillustrated in FIGS. 1 a, 1 b, and 1 c. The drive unit includes anelectric motor having a rotor shaft 2, which is surrounded by a housing1. The electronic circuit for powering and controlling the electricmotor is substantially protected by housing part 3, which has anindentation 6 in which a primary conductor is secured, using a windingloop. The return line, i.e., the second primary conductor, is only leadthrough, i.e., not wrapped around the drive unit.

Housing part 3 includes a core 7 having a U-shaped cross-section, aroundwhich a secondary winding is arranged that powers the electroniccircuit. Therefore, the drive unit may be powered by the inductivecoupling in a contactless manner, and is therefore galvanicallyseparated from the primary circuit. The power supply of the drive unitmay be disconnected rapidly and easily by unwinding or taking down theloop of the primary conductor.

The primary circuit is powered by a device, which exhibits acurrent-source behavior with respect to the primary current generated byit.

In further exemplary embodiments of the present invention, informationis transmitted by modulating higher-frequency signals onto the primaryconductor, as the electronic circuit includes device(s) for demodulatingthe signals. To exchange information, the electronic circuit alsoincludes modulation device(s), which means that signals may also bemodulated onto the primary conductor.

In this manner, the drive unit may be powered in a contactless manner.The consequence of this is that a powering principle may be realized inindustrial systems and/or machines, in which during the installation ofthe drive units, these no longer need be electrically connected andwired with the aid of expensive plug-and-socket connectors, but ratherit is sufficient for a primary conductor to be wrapped around in theindentation of the drive unit.

In addition, a high degree of protection may be realizable, sinceplug-and-socket connectors are eliminated and the drive unit maytherefore be inexpensively manufactured, along with its housing, so asto be impervious. Therefore, the drive unit may be manufactured to have,e.g., a smooth housing and is consequently usable in asepticapplications or wet applications.

Device(s) for potential segregation and other separating devices may beeliminated, since the wall thickness of the housing may be appropriatelydimensioned and the inductive coupling may be easily disconnected.

The electronic circuit also includes the secondary-side device(s) fortransmitting power inductively, i.e., without contact. These devices mayinclude passive components, i.e., capacitors and windings about coilcores. In a simple arrangement, the transformer head is wrapped with awinding in the form of a secondary winding, and a capacitor, whosecapacitance is in resonance with the inductance of the winding, isconnected in outgoing circuit, the resonance frequency corresponding tothe frequency of the alternating current in the primary conductor ordeviating from it by not more than, e.g., 10%.

The drive units may be powered in series by the primary conductor. It ispossible to decouple individual motors without having to interrupt thepower supply of the others. It may only be necessary to remove theprimary-conductor loop around the drive unit, e.g., by lifting theconductor loop out of the indentation.

The wiring hereof may eliminate the need for T-pieces.

The drive unit is illustrated as a rotary drive in FIGS. 1 a, 1 b, and 1c. The drive unit may be implemented as a linear drive and may beinductively powered.

As illustrated in FIGS. 2 a, 2 b, and 2 c, cores 27, 28 having aU-shaped cross-section may be located on the B-side with grooves forprimary conductors 21 and 22. A clip 23 is used for fixing the primaryconductors in position in their grooves. Only one core 27 may benecessary for functioning. Additional core 28 increases the efficiencyof the entire device. The secondary windings on the two cores 27, 28 areinterconnected and power the electronic circuit, which is, in turn,situated in the region of housing cover 26 that is provided on theB-side of housing 1.

As illustrated in FIGS. 3 a, 3 b, 3 c, 3 d, 3 e, 3 f, 3 g, and 3 h,which illustrate different views, some that mask material components asin FIG. 3 b, first primary conductor 32 is arranged in a cable duct 34,which is provided in a semi-loop pointing upwardly. Second primaryconductor 33 is arranged in a corresponding semi-loop pointingdownwardly. For purposes of inductive coupling, an E-shaped core 36 isprovided in the upper semi-loop, and a second E-shaped core 35 isprovided in the lower semi-loop, e.g., in the material of the cover. Thelegs of the E of the E-shaped cores are brought forward to housing part37. Housing part 37 protects a printed circuit board that carrieswindings, which extend in the shape of a spiral, are produced asconductor tracks, and are provided as secondary windings. For example, aflat, E-shaped core is placed on this printed circuit board and orientedsuch that its legs meet the legs of E-shaped core 36 when extended.Therefore, a highly effective, inductive coupling is attainable, asindicated in FIG. 3 i. The printed circuit board may also be fitted withadditional electronic components.

The function of cover 31 illustrated in FIG. 3 a is to providemechanical protection, and to be a clamping device, i.e., strain-reliefdevice. In FIG. 3 b, the material of cover 31 is omitted, so thatE-shaped cores 35, 36 are visible, as well as cable ducts 34. The covermay be detachably screwed to housing 1.

The cover may include magnetically conductive material for improvedenergy coupling. For example, this material may also be formed in theshape of a U or E.

Primary conductors 32, 33 in the cable ducts may be provided withencapsulating material for fixing them in position and sealing them.

Illustrated in 5 a, 5 b, 5 c, 5 d, 5 e, 5 f, and 5 g are different viewsof an industrial system of an example embodiment of the presentinvention, which may include drive units as described above.

In this context, a turntable 41 driven by turntable drive 42 isrotatable relative to stationary coil cores 45, which carry a coil forgenerating a medium-frequency, alternating field. The primary conductorpasses through stationary coil core 45 and is therefore inductivelycoupled to the coil. In this manner, power may be transmitted in acontactless manner from the coil to primary conductor 43, which leads,in turn, to drives 44 and powers them in a contactless manner. This mayprovide that in wet applications or aseptic applications, or in thefood-processing and luxury-food industries, the system may therefore bemanufactured to provide a particularly high degree of protection and tobe easily cleanable. In addition, the primary conductor may be installedsimply and rapidly, and the manufacturing costs and maintenance costs ofthe entire system may therefore be reducible.

The primary conductor may be arranged in a closed path and may be woundaround each drive unit once.

A corresponding, further exemplary embodiment of the present inventionis illustrated in FIG. 4.

In exemplary embodiments of the present invention, the primary conductoris wound several times around a drive unit 44.

In exemplary embodiments of the present invention, primary conductor 43is powered by a loop line instead of in a contactless manner.

As illustrated in FIGS. 4 and 5, the drive units are mounted on aturntable 41. However, exemplary embodiments of the present inventionalso provide for the drive units to be positioned under the turn tableor at other locations.

In exemplary embodiments of the present invention, a linearly movabletable, on which the drive units are positioned, is provided in place ofthe turntable. The coil cores are positioned along the path of motionand power the primary conductor that is arranged in a substantiallylinear manner.

In exemplary embodiments of the present invention, such as thoseillustrated in FIG. 4 or FIG. 5, at least one different drive unit, suchas that illustrated in FIG. 2 or 3 is used in place of the drive unitsillustrated in FIG. 1.

The method for contact-free energy transmission and the correspondingcomponents may be implementable according to the features described, forexample, in German Published Patent Application No. 100 53 373, GermanPublished Patent Application No. 103 12 284, German Published PatentApplication No. 103 12 792, German Published Patent Application No. 10339 340, German Published Patent Application No. 103 38 852, GermanPublished Patent Application No. 103 49 242, German Published PatentApplication No. 103 44 144, German Published Patent Application No. 4446 779, or also PCT International Published Patent Application No. WO92/17929. In this context, it may be provided to use a medium frequencyof approximately, e.g., 15 to 30 kHz. The adapter circuit following thetransformer head, including the coil core, may be manufactured to bepassive, i.e. without electronic power semiconductors.

1. A system, comprising: drive units arranged on a movable part, eachdrive unit powered in a contactless manner by an inductive coupling toat least one primary conductor; wherein the at least one primaryconductor is removably fixed to the drive units on the movable part, theat least one primary conductor being provided in at least one of (a) anindentation and (b) a cable duct of the drive unit.
 2. The systemaccording to claim 1, wherein the movable part includes at least one of(a) a turntable and (b) a linear drive.
 3. The system according to claim1, wherein the movable part is one of (a) rotationally mounted and (b)linearly movable.
 4. The system according to claim 1, wherein theprimary conductor is adapted to power the drive units in series.
 5. Thesystem according to claim 1, wherein at least one of (a) the primaryconductor is supplied with energy in a contactless manner by stationarycoil cores including at least one coil winding and (b) the primaryconductor is supplied with energy by a loop wire.
 6. The systemaccording to claim 1, wherein the primary conductor is arranged as aclosed loop.
 7. The system according to claim 1, wherein at least onedrive unit includes an electric motor and an electronic circuit adaptedto power the electric motor, the drive unit powered inductively.
 8. Thesystem according to claim 1, wherein a primary conductor is provided onthe drive unit such that an inductive coupling to a secondary windingincluded in the drive unit is providable.
 9. The system according toclaim 1, wherein at least one secondary winding is wound around at leastone of (a) a U-shaped and (b) an E-shaped core.
 10. The system accordingto claim 1, wherein the primary conductors are at least one of (a)partially encapsulated and (b) protected by a cover.
 11. The systemaccording to claim 1, wherein at least one drive unit is arranged atleast one of (a) impervious, (b) smooth on an outer surface, (c) toprovide a high degree of protection and (d) for use in at least one of(a) wet areas and (b) aseptic areas.
 12. The system according to claim1, wherein the drive unit does not include a plug-and-socket connectoror other electrical connection terminals on its exterior.
 13. The systemaccording to claim 1, wherein the drive unit is arranged such thatinformation is transmittable by modulating higher-frequency signals ontothe primary conductor.